This test detects the presence of antibodies in the blood to cytomegalovirus, also called CMV.
The body produces antibodies to defend against bacteria, viruses, and other harmful foreign particles. The body produces large amounts of antibodies during infections. A person's blood can be analyzed for particular antibodies. Their presence indicates that the person has been exposed to that infection-causing particle.
The CMV test is performed when a doctor suspects a CMV infection may be present. CMV usually only causes serious infections in people who have a weakened immune system for one of these reasons:
In order to test for CMV antibodies, a blood sample is needed. The blood is usually drawn from a vein in the forearm or the hand. First, the skin over the vein is cleaned with an antiseptic. Next, a strong rubber tube, called a tourniquet, is wrapped around the upper arm. This enlarges the veins in the lower arm by restricting blood flow. A thin needle is inserted into a vein, and the tourniquet is removed. Blood flows from the vein through the needle and is collected in a syringe or vial. After the needle is withdrawn, the puncture site is covered for a short time to prevent bleeding. The sample is sent to the lab to be analyzed.